Rear sight and latch for firearms



9 w. A. SCHAICH 2,446,555

REAR SIGHT AND LATCH FOR FIREARMS Original Filed Oct. 10, 1945 ..1 Figri F5 J6 Wilbur A E| Ehui Eh Patented Aug. 10 1948 S ATS TENT FFiCEOriginal application October 10, 1945, Serial No. 621,647. Divided andthis application May 12, 1947, Serial No. 747,580

10 Claims.

The invention as described herein may be manufactured and used b or forthe Government for governmental purposes without the payment to me ofany royalty thereon.

This invention relates to a rear sight and latch combination for afirearm wherein the latch yieldingly positions the rear sight whilelocking the receiver to the breech block.

This application is a division of my application for Automatic firearm,Serial No. 621,647, filed October 10, 1945.

It is an object of this invention to provide a rear sight and latchcombination for a firearm wherein the latch yieldingly retains the rearsight in both windage and rocked over positions.

Another object of this invention is to provide a simple and positivespring-pressed latch to look a stock member to the breech block of afirearm; to look a tubular receiver to the breech block; and to positionthe rear sight both in its windage and its rocked over movements.

A particular object of this invention is to provide a rear sight andspring-pressed latch combination for a firearm of the type disclosed inmy copending application for Automatic firearm, Serial No. 621,647,filed October 10, 1945.

The specific nature of the invention as well as other objects andadvantages thereof will clearly appear from a description of a preferredembodiment as shown in the accompanying drawings in which:

Fig. 1 is an enlarged fragmentary view of a firearm, partly inlongitudinal section, showing the rear sight and latch.

Fig. 2 is a section taken along line 2--'2 of Fig. 1.

Fig. 3 is a top view of Fig. 1.

Fig. 4 is a detail rear end view of the latch showing the serratedsurface thereon.

Referring to Fig. 1 there is shown in assembled relation a firearmhaving a breech block i comprising a substantially cylindrical member. Acup-shaped recess is provided therein having interior threads It tocooperate with suitable threads provided on the rear end of a tubularreceiver l2. The base [3 of such recess has a cylindrical cartridgeseating recess Hi centrally formed therein. The rear periphery of breechblock I0 is provided with threads 43 by means of which a stock supporttube 2'! is secured to breech block ll].

A flat surface I5 is provided on the top forward portion of breech blockIn and on this flat surface a rear sight base member I6 is rigidly (Cl.42r-1) (Granted under the act of March 3, 1883, as amended April 30,1928; 370 0. G. 757) secured, as by welding or brazing. Rear sight base15 is generally U-shaped in cross-section, having a base portion i1 andtwo laterally spaced, upstanding sight arm portions it and itrespectively. Longitudinally extending through base portion I! is a hole29 having the rear end portion thereof counterbored as indicated at 25.

A latch plunger 22 is slidably mounted in hole 20. Plunger 22 has anenlarged head portion 23 which cooperates in bearing relationship withthe counterbore 2|. A generally rectangular latching head 25 isthreadably secured to the forward end of plunger 22 which projects outof the hole 20. A spring 25 operates between head portion 23 of plunger22 and the base of counterbore 2| to impart a rearward bias to theplunger 22 and latching head 24.

In its normal position, the head portion 23 of plunger 22 projects outof the rear of the sight base l6 and cooperates with a slot 25 in thestock tube 21 to lock such tube to the breech block 10. The head portion23 of plunger 22 may, however, be disengaged from the stock tube bypushing the plunger forwardly against the bias of spring 25.

The bottom portion of latching head 2 in its normal position, projectsdownwardly through a slot 28 provided in breech block It and a slot 29provided in the tube 52. Thus the latching head 24 will prevent relativerotation of the tube 12 with respect to the breech block iii and hencemaintain these components in proper assembled relationship. The depth ofthe slots 28 and. 29 are proportioned so that the latching head '2?! maybe disengaged from the receiver by forward movement of the latch againstthe bias of spring 25, followed by rotation of A rear sight 3!) ismounted between arm portions l8 and I9 upon a transverse screw 3!. Screw3! is journaled in arm portions !8 and i9, and on the left-hand sidethereof as viewed in Fig. 2, is provided with an integral, enlarged knob32. A locking ring 33 is snapped into a groove 34 provided in the end ofscrew 3| projecting through arm portion I9 and thus prevents the removalof the screw 3! from the rear sight base [6.

The rear sight 30 may comprise any of several well-known types of sightshaving self-contained elevational adjustment means for a sight aperture35. Such elevational adjustment of the aperture may, for example, beobtained by rotation of a sight operating sleeve 36. The details of theelevational adjustment of the aperture 35 comprise no part of thisinvention and will not, therefore, be further described.

Sight 30 has a depending tongue portion 31 through which is provided athreaded transverse hole 38 which cooperates with the screw 31 toprovide windage adjustment of the sight by rotation of knob 32. Thesight 30 is resiliently latched in either an upright position or arocked over position through the cooperation of the upper portion of thelatching head 24 with tongue portion 31. The juncture of bottom andfront surfaces 39 and 40 respectively of the depending tongue portion 31of the sight 30 is suitably shaped so that rotation of the sight betweenits upright and rocked over" positions will produce a forward movementof the latching head 24 against the bias of spring 25. In addition, thefront surface 4!) of the sight is provided with a plurality of verticalserrations M which are engaged by similar serrations 42 in the rearlatching face of the top portion of latching head 24. Thus the latchinghead 24 also serves to resiliently secure the sight in any selectedwindage position. Turning of the windage knob 32 produces a transversemovement of the entire rear sight and hence cams the latching head 24forwardly against the bias of spring 25 a suflicient distance to permitserrations ii and 42 to disengage and then re-engage at a new positionone or more notches displaced from the original position. The spacing ofthe serrations 3! and 42 may be conveniently selected to correspond withany desired increment of minutes of angle, such, for example, as havingthe space between two adjacent serrations correspond to an azimuthalsight deflection of one-half minute of angle.

From the foregoing description it is clearly apparent to those skilledin the art that there is here provided a unique rear sight and latchingarrangement for a firearm. The latch member positively yet yieldinglysecures the rear sight in a rocked over position and in any desiredwindage setting. Such latch also positively aligns and locks thereceiver of the firearm to the breech block while at the same timelooking a stock support member thereto. The construction of this sightand latch combination is such as to lend itself to ease of manufactureand being of simple and rugged construction does not easily get out oforder and will perform its function in a highly satisfactory manner.

I claim:

1, In a firearm having a breech member and a receiver member threadablysecured thereto, the improvement comprising a sight base formed on thebreech member, said sight base including a pair of upstanding,transversely spaced brackets, a sight adjusting screw journaled in saidbrackets, a sight member supported on said screw, and a spring pressedlatch having one portion thereof engageable with said sight member toresiliently position said sight member in any selected azimuth positionand another portion engageable between the receiver and breech membersto lock such members against relative rotation.

2. In a firearm having a breech member and a receiver member threadablysecured thereto, the improvement comprising a sight base formed on saidbreech member, said sight base including a pair of upstanding,transversely spaced brackets, a sight adjusting screw journaled in saidbrackets, a sight member supported on said screw, said sight base havinga longitudinally extending hole therein, a spring pressed plungermovably mounted in said hole, and a latching head portion on saidplunger, said latching head portion being constructed and arranged toresiliently engage and position said sight member in any selectedazimuth position, said latching head portion also being engageablebetween the receiver and breech members to lock such members againstrelative rotation.

3. In a firearm, a generally cylindrical breech member, a tubularreceiver member threadably secured to the forward end of said breechmember, a tubular stock member threadedly secured to the rear end ofsaid breech member, and a spring pressed latch engageable between saidbreech member and said receiver member and also between said breechmember and said stock member to lock such members against relativerotation.

4. In a firearm, a generally cylindrical breech member, a tubularreceiver member threadably secured to the forward end of said breechmember, a tubular stock member threadably secured to the rear end ofsaid breech member, said breech member having a longitudinal holetherein lying between the facing ends of said receiver member and saidstock member, said receiver member and said stock member each having alongitudinal slot therein disposed in alignment with said hole in theassembled positions of said receiver member and said stock memberrelative to said breech member, a spring pressed plunger movably mountedin said hole, and a latching head portion on each end of said plunger,said head portions respectively engaging said slots thereby locking saidreceiver member and said stock member against rotation relative to saidbreech member.

5. A firearm, a generally cylindrical breech member, a tubular receivermember threadably secured to the forward end of said breech member, atubular stock member threadably secured to the rear end of said breechmember, a sight base formed on said breech member, said sight baseincluding a, pair of upstanding, transversely spaced brackets, a sightadjusting screw journaled in said brackets, a sight member supported onsaid screw, a spring pressed latch having a first portion thereofengageable with said sight member to resiliently position said sightmember in any selected azimuth position, a second portion engageablebetween said receiver and breech members to lock such members againstrelative rotation, and a third portion engageable between said stock andbreech members to lock such members against relative rotation.

6. In a firearm, a generally cylindrical breech member, a tubularreceiver member threadably secured to the forward end of said breechmember, a tubular stock member threadably secured to the rear end ofsaid breech member, a sight base formed on said breech memberintermediate said stock and receiver members, said sight base includinga pair of upstanding, transversely spaced brackets, a sight adjustingscrew journaled in said brackets, a sight member supported on saidscrew, said sight base having a longitudinal hole therethrough, saidreceiver member and said stock member each having a longitudinal slottherein disposed in alignment with said hole in the assembled positionsof said receiver member and said stock relative to said breech member, aspring pressed plunger movably mounted in said hole, and a latching headportion on each end of said plunger, said head portions respectivelyengaging said slots thereby locking said receiver member and said stockmember against rotation relative to said breech member, one of said headportions also engaging said sight memher to resiliently position saidsight member in any selected azimuth position.

7. For use in a firearm, a sight base member having a pair ofupstanding, transversely spaced bracket portions, a windage adjustmentscrew journaled in said bracket portions, a sighting member threadablysupported on said screw and having two selective operating positionsangularly displaced about the axis of said screw, said sight base memberhaving a longitudinally extending hole therein, a plunger movablymounted in said hole, a latching head on said plunger having a latchsurface disposed adjacent the pivoted end of said sighting member, andresilient means for biasing said plunger axially whereby said latchsurface of said latching head is resiliently held in engagement withsaid sighting member to latch said sighting member in either of itsselective angular positions.

8. The combination defined in claim 7 wherein said latch surface and theabutting surface of said sighting member are provided with a pluralityof mutually engageable, transversely spaced serrations whereby saidlatching head resiliently secures said sighting member in any selectedone of a plurality of windage positions on said windage screw.

9. In a firearm, a generally cylindrical breech member, a tubularreceiver member threadably secured to the forward end of said breechmember, a tubular stock member threadably secured to the rear end ofsaid breech member, a sight base formed on said breech member, saidsight base including a pair of upstanding, transversely spaced brackets,a sight adjusting screw journaled in said brackets, a sighting memberthreadably supported on said screw and having an upright sightingposition and a rocked over position angularly displaced about the axisof said screw, said sight base having a longitudinally extending holetherein, a plunger movably mounted in said hole, a latching head on saidplunger having a latch surface disposed adjacent the pivoted end of saidsighting member, resilient means for biasing said plunger axiallywhereby said latch surface of said latching head is resiliently held inengagement with said sighting member to latch said sighting member ineither of its angularly displaced positions, a depending portion on saidlatching head engageable between said breech and receiver members tolock such members against relative rotation, and a latching head portionon the rear end of said plunger engageable between said breech and stockmembers to lock such members against relative rotation.

10. The combination defined in claim 9 wherein said latch surface andthe abutting surface of said sighting member are provided with aplurality of mutually engageable, transversely spaced serrations wherebysaid latching head resiliently secures said sighting member in anyselected one of a plurality of windage positions on said sight adjustingscrew.

WILBUR A. SCI-IAICH.

